I tried -copyright, but I still had things like the Trix rabbit, who was properly tagged with a purple Copyrighted Twix character tag, show up in my search. I don't want to blacklist every single copyrighted tag; I only want to omit them from one search to see every post without a commercial character, like Bugs Bunny or Nick Wilde. Sure it might block things like whitekitten posts, which might not have any commercial characters, but it would still allow the majority of posts through.